A monolithic optical component is a singular device which is relatively compact and has a relatively stable nature. The functionality of the monolithic component is typically incorporated in the formation of the component, such that the monolithic component is adapted into any optical system by performing the same function independent of the optical system. Monolithic optical components are often produced from a single piece of homogeneous material by precisely fabricating each optical surface. Because of this construction, it may enjoy certain homogeneous material properties that allow the monolithic optical component to operate as intended, despite minor environmental perturbations, such as acceleration, temperature fluctuations, and pressure changes.
Despite the recognized performance advantages of using monolithic optical components in high-precision optical systems, there are significant shortcomings to these components, which may affect their selection for particular optical systems. Such shortcomings may include lack of flexibility and high cost. Because the monolithic optical components require a certain amount of homogeneity, the fabricated component may be restricted to function only in a simple configuration. Further, under the exposure of uneven environmental perturbations (i.e., large temperature gradients, unbalanced stress states, etc.), the absolute homogeneity of the component may be undermined, which the monolithic optical component itself may not have the flexibility to correct or compensate for. The monolithic optical component also requires skilled opticians and/or sophisticated equipment to produce the high-quality surface finish, often in multiple dimensions, necessary for a high-precision component. Accordingly, the manufacturing cost can be high even for a component of moderate complexity. As the complexity of monolithic optical components increases, so may the associated costs increase. Any special configurations, ultra-high precision requirements, large size, or increased number of optical-quality surfaces could also dramatically increase manufacturing costs.
As a result, many complex optical systems are constructed as adjustable optical assemblies. For example, separate monolithic components in adjustable or reconfigurable form can allow for the selection components with various material and optical properties. Furthermore, the adjustable assemblies can enable the integration of complex and flexible configurations, which may perform various functionalities, while also allowing for the compensation of environmental perturbations. However, the size and complexity of these adjustable assemblies can be a deterrent in some applications. Moreover, the stability of adjustable systems can be compromised by their flexible and adjustable nature. As these instabilities can be undesirable, active control systems may be required, thus adding to the expense and complexity of adjustable optical assemblies.
A monolithic optical assembly is the integration and attachment of several individual monolithic components, which are precisely aligned to serve as a single optical unit. These individual components may be affixed after alignment. For example, the individual components may be aligned with the assistance of mechanically-adjustable tools or fixtures, after which the components may be secured together in fixed position relative to each other. The fixed position can be reconfigured and re-secured to adapt to different applications, as necessary. Thus, monolithic optical assemblies may combine the benefits of monolithic optical components, and adjustable optical assemblies.
However, there are many challenges in the manufacturing process of a monolithic optics assembly. For example, fixtures and components must be maintained in a high degree of stability during the alignment and securing processes. This includes releasing loaded force and torque from the assembly after the alignment is fixed. In addition, misalignment and drift tendencies caused by non-homogeneous thermal expansion among constructing fixtures and components must be avoided.
Accordingly, there is a need for high-precision optical components that can provide drop-in functionality akin to monolithic optical components, but at a reduced manufacturing cost. There is also a need for a high-precision optical component that combines the stability of monolithic optical components with the flexibility of an adjustable optical assembly.